In the field of medical devices, many medical devices utilize a connector having a pair of one-way valves therein. For example, in hospital pharmacies, it is oftentimes necessary to dilute or reconstitute a large number of medications. In order to expedite and reduce the cost of this procedure, a large bulk container of diluent, such as sterile water or normal saline, may be used. The bulk container is typically attached to a medical device having an inlet for the bulk container, a luer-type of connector for a syringe and an outlet which may be attached to a medication containing vial or an IV bag. These medical devices typically include a first one-way valve positioned between the inlet and the luer connector and a second similarly oriented one-way valve positioned between the luer connector and the outlet to enable the user to withdraw the desired amount of diluent from the bulk container into the syringe and then from the syringe into the vial or IV bag through the outlet of the medical device.
Variations of this medical device may also be used to transfer small amounts of fluid from a fluid reservoir into a medical device such as a closed system suction catheter to assist in the aspiration of the patient or to facilitate the removal of mucous from the interior and/or exterior of the catheter. Another use of a medical device having a pair of one-way valves positioned therein is illustrated in U.S. Pat. No. 4,921,488 granted to Maitz et al. The Maitz et al patent discloses the use of a squeeze bulb in combination with a meconium aspirator to remove meconium fluid from a baby during or shortly after delivery. The squeeze bulb disclosed in this patent includes a pair of one-way valves to allow the user to manually remove the air from the bulb when the bulb is squeezed and to apply a vacuum pressure to the aspirator when the bulb is released so that the fluids will be drawn from the patient into a collection device. In the Maitz et al. device, the one-way valves are usually constructed as flapper or duck bill type valves. These duck bill valves each consist of a pair of rubber members which are biased to close against each other as shown in the above-described Maitz et al. patent.
Another medical device which uses a pair of check valves is disclosed in U.S. Pat. No. 3,957,052 granted to Topham. In the Topham device, a pair of valve balls are used to selectively allow the flow of fluid between a needle and a syringe and then between the syringe and a container or collection vessel. The first valve ball of this device is movable between a first position adjacent to the opening of the syringe and a second position adjacent to the opening of the needle. In this device, when the first valve ball is in the first position, fluid is allowed to flow around the valve ball from the needle to the syringe. When the first valve ball is in the second position, fluid is prevented from flowing around the valve ball and into the needle. The second valve ball is retained adjacent to the opening of the container and is movable between open and closed positions.
Although the above described valves are adequate for most procedures, the use of two separate valves in each device increases the cost of the device and may also increase the likelihood that one of the valves may stick in either the open or closed position.